| FR | failure rate; film-screen radiograph; fasciculus retroflexus; febrile reaction; feedback regulation;... |
|---|---|
| OR | a logical binary relation that is true if any argument is true, and false otherwise; [o]estrogen rec... |
| ORE | oil retention enema |
| RC | an electronic circuit containing a resistor and capacitor in series; radiocarpal; reaction center; r... |
| REEDS | retention of tears, ectrodactyly, ectodermal dysplasia, and strange hair, skin and teeth [syndrome] |